Catalyst for synthesis of ammonia



Patented June 22,1926. A

UNITED STATES PATENT OFFICE.

TVAR WALFRIID CEDERIBERG, OF LIDINGO-IBREVIK, NEARSTOCKHOLM, SWEDEN, AND I MIKAL FJELLANGER AND VILHELM GR'U'NER, OF SKOIEN, NORWAY, ASSIGNORS TO NORSK HYDRO-ELEKTBISK KVAELSTOFAKTIESELSKAB, OF CHRISTIAN IA, NOR- WAY.

CATALYST FOR SYNTHESIS OF AMMONIA.

No Drawing. Application filed September 7, 1921, Serial- No. 498,968, and in Norway September 7, 1920.

This invention relates to a catalyst useful salt present, so as to have no excess of heavy to in. the synthesis of ammonia from nitrogen metal salts, or one will have to Wash the and h drogen. product until the soluble simple heavy metal In erman Patent No. 285,698 is described salts are removed.

I a method for producing ammonia by the The precipitate can be placed directly'in use of catalysts containing alkali metal or the contact furnace, where the heating takes 85 alkali earth metal ferroeyanides or ferriplace in an atmosphere free from oxygen. eyanides. These catalysts Work at low temperatures,

It is stated in said patent that the effect below 400 0., and pressures below 100 at- 10 produced is specific to these compounds, and mospheres.

that the ferroc anides or ferricyanides of We claim 40 the heavy meta s, for example Berlin blue 1. Catalyst for the production of ammonia (ferri-ferro cyanide), have only a weak from nitrogen and hydrogen, comprising contact efiect. a precipitate resulting from complex iron 15 The present invention is based upon the cyanides and simple heavy metal salts, said discovery that these compounds, the heavy preci itate being free from simple heavy 45 metal ferroand ferri-cyanides which are .meta salts and heated under pressure in insoluble in water will act catalytically, proan atmosphere free of oxygen. vided they are freed from the soluble simple 2. Method of producing a catalyst for the 20 heavy metal salts. Such soluble simple roduction of ammonia from nitrogen and heavy metal salts have an intense reducing ydrogen, consisting in precipitating sim 1e 50 or poisoning influence on the catalytic efl'eet heavy metal salts with an excess of comp exof the compound in question. iron cyanides, and heating the precipitate in If it is desired to roduce a usable cataan atmosphere free from oxygen. 25 lyst, one will have eit er to efiect precipita- In testimony that we clalm the foregoing H tion from the soluble ferroor fern-cyanide, as our invention, we have signed our names. e. g., potassium ferroor ferri-cyanide, with IVAR WALFRID CEDERBERG. heavy metal salts in such a way that there MIKAL FJELLANGER.

is always a surplus or excess of cyanogen VILHELM GRUNER. 

